According to the Arizona Republic, tourists, including children, were exposed to uranium ore that were contained in three five gallon buckets, one of which had so much ore in it that the lid did not fit, in the Grand Canyon Museum’s collections building. Not one tourist and, I assume NPS staff, were never advised they were exposed to unsafe levels of radiation. The buckets, held in the basement of the building for a decade or two, were for some reason, moved into the museum itself in 2000. They were stored in the taxidermy collection where young kids sat nearby for a half hour listening to presentations by NPS staff.
According to the whistleblower, the children were exposed to high levels of radiation within 3 seconds, and adults would have had dangerous amounts of radiation exposure within 30 seconds.
The Nuclear Regulatory Commission measures radiation contamination in millisieverts per hour or per year. According to Stephenson, close exposures to the uranium buckets could have exposed adults to 400 times the health limit — and children to 4,000 times what is considered safe.
Last year, officials were made aware of the buckets of radiation in the museum. It was then the buckets were loaded into a pickup truck by workers who were not provided with protective clothing or gloves.
Technicians did not have protective clothing, so they purchased dish-washing and gardening gloves from a general store. They then used a broken mop handle to lift the contaminated buckets into a truck, Stephenson saidIn a rogue email sent to all Park Service employees on Feb. 4, Elston "Swede" Stephenson — the safety, health and wellness manager — described the alleged cover-up as "a top management failure" and warned of possible health consequences.
"If you were in the Museum Collections Building (2C) between the year 2000 and June 18, 2018, you were 'exposed' to uranium by OSHA's definition," Stephenson wrote. "The radiation readings, at first blush, exceeds (sic) the Nuclear Regulatory Commission's safe limits. … Identifying who was exposed, and your exposure level, gets tricky and is our next important task."
snip
Stephenson calculated potential exposures over 1,400 times the NRC's safe level for children, and over 140 times the safe level for adults.
He said he pressed park superintendents to take action, submitted an Inspector General complaint, contacted the FBI, and wrote to every member of Congress.
In his letter to colleagues, Stephenson apologized for the untimely notice. He stressed that exposure may not be severe depending on how close individuals got to the source, how long they were exposed, what they were wearing, and other factors. He also emphasized that employees will not necessarily suffer health consequences, but should consider receiving a medical screening.
"Of particular concern are 1000s of children attending 'shows' in very close proximity to the uranium," he wrote. Those presentations lasted a half hour or more, he said, yet radiation dosages could have exceeded federal safety standards within seconds.
"They're in cover-up mode," he said. "I've been cut off from any kind of information."
You could hear their meters going off," Stephenson said about the three buckets in the museum building.There is an interesting video in the source link. I am unable to embed it here.